Evaluation of self-reported dominance in upper and lower limbs and its relationship with fatigue onset in dominant limbs using surface electromyography (sEMG) in young adults.

Abstract

Background: "Laterality", or "lateral preference" indicates how differently or rather 'differentially' one tends to use a pair of sense organs or limbs. The most widely studied aspect of laterality is handedness. However, research on footedness has not received the same level of attention. Previous studies primarily relied on questionnaires to determine limb dominance, which may not provide the most accurate assessments. The present study aims to generate reliable objective data regarding both upper and lower limb dominance by analyzing surface electromyography (sEMG) parameters. Additionally, it seeks to correlate these findings with perceived limb dominance as indicated by questionnaire responses.

Methods and material: It was a cross-sectional observational study. The physiological parameters were recorded in the Clinical Physiology Laboratory. 20 male, healthy participants of 19-20 years participated in the study voluntarily. After recording of their demographic data, the study participants were assessed twice to ascertain the dominance of both upper and lower limbs. At first, they responded to the study questionnaires to report self-determined dominance of upper and lower limbs. Following this, the performance of both upper and lower limbs was evaluated by recording of surface EMG of specific muscles of the limbs at rest and during sustained contraction using a pre-defined load till the onset of fatigue. On the basis of normality test, the data were expressed as median with interquartile range. Wilcoxon signed rank test was performed to compare the parameters of sEMG. SPSS software version 20.0 (IBM Inc., USA) was used to analyse the data. A two-tailed P value less than 0.05 was taken as the cut-off level of significance.

Results: Based on questionnaire analysis, out of 20 participants, one was left-handed and the rest were right-handed. Six participants were found to use both legs and the rest were right leg dominant. Following analysis, no significant difference between the parameters of surface EMG (sEMG) of the corresponding muscles of the two upper and lower limbs was found. Even no significant difference between the time to set fatigue in right and left upper and lower limbs was observed.

Conclusions: The result of the present study indicates that the dominant and the non-dominant limbs have attained differences in such a manner that it has not affected their performances significantly. However, their different, though sometimes overlapping aspects of motion and movements is helpful for the performance of a given task.